180 likes | 361 Views
CLS 1113 Introduction to Clinical Laboratory Practices. Unit 4 Introduction to Immunology. Immunology. Immunology: Study of the molecules , cells , organs , and systems responsible for the recognition and disposal of foreign (nonself) material
E N D
CLS 1113Introduction to Clinical Laboratory Practices Unit 4 Introduction to Immunology
Immunology • Immunology: • Study of the molecules, cells, organs, and systems responsible for the recognition and disposal of foreign (nonself) material • Study of the MECHANISMS that protect an individual from injury from: • Exogenous microorganisms – bacteria, fungi, viruses • Exogenous chemicals – pollen, poison ivy, etc. • Endogenous cells – malignant or senescent cells • IMMUNE RESPONSE: Broad range of defense mechanisms including inflammation, phagocytosis, antibody synthesis, etc.
Serology • Serology: the study of the non-cellular components of the blood (serum). • Antibody production and reactivity • Complement
Natural Immunity • Innate or Inborn immunity • Non specific • External Defenses: • Skin, acid in sweat, mucus membranes, cilia in respiratory tract, normal flora • Internal Defenses: • Non-specific cellular responses • Cells and soluble factors
Acquired Immunity Active • Allows the body to Recognize, Remember and Respond to a specific stimulus. • Example: Your Hepatitis B shots (You were give three doses of attenuated Hep. B virus; your body recognized it as foreign and produced an anti-hepatitis B antibody.) Passive • Antibody mediated immunity received from another source • Example: A mothers breast milk has antibody that the baby uses until he/she can produce their own. • Example: A gamma (immune) globulin shot provides immunity when someone travels over seas, but their body did nothing to develop the immunity.
Cell Mediated vs.Humoral Immunity Cell Mediated Immunity • Form of acquired immunity in which T lymphocytes recognize and react with a stimulus through direct cell-to-cell interaction of lymphokines. Humoral Immunity • Form of acquired immunity in which B Lymphocytes and plasma cells produce specific antibodies that recognize and react to a stimulus.
Cellular Immunity:Resistance to disease via cellular elements (Granulocytic) in the blood. Neutrophils • Neutrophils have primary and secondary granules which contain a wide variety of enzymes. • Neutrophils migrate through vessel walls (diapedesis) and into tissues when signaled by chemical messengers (chemotaxins).
Cellular Immunity Eosinophils • Red granules • Eosinophils increase in number in an allergic reaction or in response to many parasitic infections.
Cellular Immunity Basophils • Blue, large granules containing heparin and histamine • Heparin is an anticoagulant and histamine contracts smooth muscle
Cellular Immunity Monocytes • Monocytes only make up 4-10% of the circulating WBC’s. • They stay in the blood for a short period of time and then migrate out into the tissues and become known as macrophages.
Cellular Immunity Macrophages • Macrophages have specific names depending on their function and particular location. • Lung macrophages are “alveolar macrophages”. • Liver macrophages are “Kupffer cells”. • Brain macrophages are “microglial cells”. • Connective tissue macrophages are “histiocytes”. • Monocytes/Macrophages are very important. • They participate in phagocytosis, anti-tumor activity, chemical secretion, and antigen presentation.
Phagocytosis • Phagocytosis • Greek word meaning “cell-eating”The engulfment of cells or foreign matter. • Phagocytosis consists of four main steps • Physical contact of the cell with the foreign agent • Formation of a phagosome • Fusion with cellular granules • Digestion and release of debris to outside of cell
Opsonin • An opsonin (Greek word meaning “prepare for eating”) is a plasma protein that will attach to a foreign substance and prepare it for phagocytosis. Types of opsonins include: • C-reactive protein, complement, antibodies
Inflammation • Tissue reaction to injury caused by physical or chemical agents including microorganisms. • The signs of inflammation include: • Redness and Heat • Mast cells release histamine causing vasodilation increasing the blood flow to the area • Swelling and Pain • Increase permeability allows fluids to leak into the tissues
Inflammation • Major events associated with inflammation include: • Increase blood supply to the affected area • Increased capillary permeability • Migration of neutrophils to the affected area • Migration of macrophages to the affected area